1. Field of the Invention
This invention relates to devices for dispensing and mixing liquids, and more particularly to such devices that dispense and mix chemicals, and even more particularly to devices that dispense and mix cleaning chemicals.
2. Prior Art
Devices for dispensing and mixing cleaning chemicals have been recognized for several years as a major safety feature for personnel who are required to handle the chemicals. Such devices permit personnel to fill containers with cleaning products without having to come into physical contact with the chemicals that are mixed to produce the products. In addition to their safety features, these devices reduce waste and reduce spillage.
Typifying such dispensing and mixing devices is that commercially known as "Oasis" and which is distributed by Ecolab of St. Paul, Minn. The system is a single or multiple station fluid pressure operated device which dispenses to a three or five gallon mixing jug. This system is mountable on a shelf or a wall rack.
The "Oasis" device deploys a water gun, a metering device and a product concentrate tube which are assembled to and communicate with a filling jug. The product concentrate or cleaning chemical is brought to the jug through the concentrate tube. When the water gun is activated, the pressure created by the water draws the concentrate through the concentrate tube and the metering device and into the jug where it mixes with the water. After the jug is full, an operator can then fill a use solution container from a faucet or tap provided in the jug. In multiple filling stations, to prepare another cleaning chemical, the water gun is simply moved to another jug.
Processing one cleaning chemical at a time prevents cross-contamination. However, the movement of the water gun is time consuming and limits the system to processing only one chemical mixture at a time until the gun is moved to the next station. Generally, such a system is not capable of mixing and dispensing directly into a small sized container, such as a one-gallon container. Thus, there is a two-step process of mixing in one container, then dispensing into another container.
Another type of device used to mix and dispense chemicals is a siphon-type device such as that commercially made and marketed by Hydro Systems Company. Essentially, the system uses water flowing through a water valve and an eductor to draw a cleaning chemical to the educator. The water and cleaning chemical are mixed to a concentration based on the size of a metering tip disposed in the eductor. This device essentially comprises a source of water connected to a T-shaped educator, which, in turn, is in fluid communication with the source of chemical to be mixed with the water, As water flows through the eductor, it creates a vacuum, thereby drawing chemical thereinto which mixes with the water as it flows through the eductor and into a filling container. A manually operated gate, such as a spring-loaded shut-off controls the water flow through the eductor. This system eliminates the need to move a gun, but it still can only mix one chemical from a single source.
Another type of system, permitting up to four chemicals to be processed through one valve, is made and marketed by Hydro under the name "Streamline Select Four". In this system, up to four chemical sources are connected to the eductor via a single selector switch which functions as a valve. The selector switch selects the cleaning chemical to be mixed with water and is delivered therethrough to the eductor. However, the selector switch creates cross-contamination when it is changed from one chemical to another. The residue of the formerly processed chemical remains within the switch and mixes with the new chemical.
The cross-contamination is generally not a problem when filling large containers because the large amount of the new chemical significantly dilutes the former chemical. However, for small containers, such as one-gallon containers, the former chemical is usually not diluted sufficiently to meet quality and federal guidelines.
Moreover, other problems exist with present-day devices. For example:
(a) Excess operator handling to prevent cross-contamination when transferring from a large container to a small container; PA1 (b) Selector-type systems are currently not usable for small containers because of cross-contamination; PA1 (c) The known devices are primarily effective only when processing large volumes of cleaning products; and PA1 (d) Generally, multiple stations are required in order to handle multiple chemicals. PA1 (a) means for delivering water from a source thereof; PA1 (b) plural sources of chemical to be mixed with the water; PA1 (c) a first container filling station including: PA1 (d) a second container filling station for filling containers of a size different than those at the first filling station including:
Thus, it is apparent that the use of the presently known selector switches to process multiple cleaning chemical sources are practical only for large containers. It would be desirable to provide a single system that incorporates the features of the selector switch for mixing cleaning product and filling both large and small containers with the product without cross-contamination of the small volume containers.